Coating or sealing composition



- composition 'of matter suitable for use in- PATENT OFFICE.

MORTIMER I. STRAUSS, 0F CLEVELAND, OHIO.

COATING 0R SEALING COMPOSITION.

Specification of Letters Patent. Patented July 25, 1922,

No Drawing. Original application filed May 18, 1917, Serial No. 169,451. Divided and this application filed January 31, 1921.

varnish,. surface coating, or cement. More particularly the invention has relation to a preventing loss or leakage of gasoline,

kerosene, oils or the like, and for protecting the surfaces of containers or conduits in or through which they are stored or conducted.

Gasoline, kerosene, oils or the like are stored in receptacles which frequently require the use of packed or sealed joints, especially when the receptacle or tank is of knockdown construction. These materials are also conducted through pipes or conduits frequently required to be flexible and which therefore ar made or lined with rub,- ber or a composition, which also is vused for the gaskets or packings of the tanks. These -liquids exert a--deleteri0us effect upon-rubber or like materials or compositions,'which are therefore eculiarly unsuitable for the purpose for w ich they must be used, and it is difiicult, to provide a satisfactory prm tecting material for rubber or the like, but shellac, when dry, is hard and brittle and therefore cracks. and exposes the underlying material to the action of the gasoline or oils, and cannot be used where flexibility is required. Moreover it is not sufficiently adhesive, and willnot cling to certain sur- The object of the present invention is to provid a composition of matter which is wholly impervious to or unaffected by gasoline, kerosene, oils or the like; which when dry, is flexible and will bend without cracking and thereby maintains a continuous protecting surface; which is more adhesive to wood, metal, rubber, concrete, and other materials than ordinary shellac, and which can be used in several forms, for example, as a varnish or surface coating, or as a cement.

Recognizing the oil and gasoline proof qualities of shellac and similar gums, this material, to-wit, shellac or a shellac-like Serial No. 441,511.

substance, forms the basis of my improved composltion of matter, but the shellac is subjected to certain treatment to produce the improved qualities desired. Any ordinary grade or kind of shellac or similar substance may. be used although I prefer to -use what is called in the trade orange shellac. This material is first dissolved in a suitable alkaline solution, for example, caustic soda, preferably in the presence of heat to promote solution. The mixture is carefully stirred until all of the shellac is dissolved. The product of this solution is not a definite composition as it depends upon the particu lar shellac or gum used, but as all shellac is a resinous gum, the product passing into so.- lution is usually sodium resinate or a similar material. A waxy substance forms on the top of the solution'and is skimmed off or otherwise removed. This Waxy substance probably consists of impurities in the shelac, although it may contain a slight quantity of shellac itself.

The resulting solution, containing the sodium resinate, is transferred to a larger receptacl and is subjected to treatment with a suitable acid, for example dilute sulphuric acid. The quantitfy of acid used"depends uponthe amount 0 caustic soda required to produce full solution ofthe shellac, and is usually very slightly morethan enough to completely neutralize any traces of caustic soda remaining in the solution. The sulphuric acid is added slowly to the shellac solution and the product is allowed to stand until complete precipitation occurs. The water of the solution is drained ofi and the resultant precipitate is Washed once or several times wit pure Water. The precipitate is then transferred to a clean receptacle and is cooked or heated to drive off the remaining traces of water in the solution. This is primarily a-drying process the temperature not being carried sufliciently high to produce any change in the characteristics provided with suitable solid body material, preferably inert and impervious to and un affected by gasoline, oils or the like. Such material will improve the consistency of the mass and improve its spreading qualities, so that it is more readily applied with a brush. One suitable substance for this purpose is Venetian red or some other similar color material, which not only provides body and improves the spreading qualities, but also gives the material such a distinct color as to enable it to be applied more readily,

- the workman being enabled to see where the material has been applied.

The quantities of the various ingredients may be varied within reasonable limits and depend to some extent uponthe character of shellac or gum and the particular effects desired. For example, one specimen batch of material was made according to my process as follows The caustic soda solution consisted of ten (10) pounds of dry caustic soda dissolved in from ten (10) to fifteen (15) gallons of water, in which solution was dissolved thirty-six (36) pounds of orange shellac. Solution was promoted by heat and after complete solution themass was allowed to cool for one-half hour and the waxy substance removed from the top of the solution. The sulphuric acid solution was produced by slowly adding to about ten (10) gallons of water thirteen (13) pounds of oil of vitriol, 66 Baum. This sulphuric acid solution was added to the resultant solution from the first caustic soda treatment. The mixture was allowed to stand thirty minutes to produce complete precipitation, whereupon the water-was drawn off and the precipitate treated by heating gently for about one hour. The solid matter was then thinned with two gallons of 95% denatured alcohol. 7 c t It is found in practice that the quantity of dissolved and thinned shellac produced from several different batches of material,

all of the same quantities, varies within limits. The quantity of body material or coloring matter to be added therefore depends on the amount of final dissolved product. Usually about two pounds of Venetian red are added to each gallon of resultant dissolved thinned shellac, although this depends considerably upon the treatment, as the heat volatilizes or expels a certain amount of shellac and considerable experience is necessary and in various ways.

to prevent unnecessary loss.

The material produced by the method described -to this point, either with or without coloring matter, can be used immediately For example it forms a good coating material for rubber, rubber compositions or like packing materials. \Vhen rubber is used as a packing material for the joints of gasoline or like tanks, such .ings or gaskets may form an unaffected by gasoline, kerosene, oils and the I like.

The varnish is also suitable for use for coating conduits or pipes through which gasoline, oils and the like are conducted, or to protect the interior surfaces of containers therefor. It will cling to and forms a protecting coating for concrete when used as a conduit or container, and also can be applied effectively to wood, metal and other'surfaces. It also forms a very efficient coating for the inner-surfaces of rubber tubing or hose and largely prevents deterioration thereof and therefore prolongs the hose life.

When the varnish is used as a protecting coating for rubber and rubber composition or similar packing materials, it may be applied in two ways. The structure, such as a tank, conduit or the like, may be assembled with' the packing in place and the varnish subsequently applied to the exposed edges of the packing material, or the surface of the tank or conduit. It is possible, however, to apply the varnish to the packing 'material in the form of a gasket or the like before said packing material is laid in place in the joint. For example, when the packing is in,the form ofa strip or a ring-like washer the varnish may be applied as a continuous coating over the entire surface of the gasket, or may be a plied merely to the inner and outer edges of said gasket, to-wit, those edges which would be. exposed on the inner and outer surfaces of the reservoir or conduit. This leaves the two opposite or upper and lower surfaces of the gasket uncoated, the rubber exposed-on these surfaces protecting the leak-tight joint. Spch packarticle of man ufacture and'sale.

The varnish may also be modified for use as a cement, in which case it is provided with a solid body material of some inert filling substance, preferably inorganic, which is impervious to and unaffected by gasoline, oils and the like. Powdered silica and some silicates are suitable for this purpose, although I prefer to, use finely divided asbestos fibre, or some other fibrous material. The'quantity of this inert body material may vary, but approximately two and one-half (2-1 pounds to each gallon of the varnish forms'a satisfactory cement. When the substance is mixed with the varnish the fibres interlock as a firm body embedded in the varnish, and the dried material. utilized as a cement in the joint, renders the joint leak proof and impervious to gasoline. oils or the like. This cement, for example, can be applied to interlocking joints in metal receptacles, a thin coating sufficient to cover all exposed interlocking or concealed surfaces being sufficient. The inert filling material prevents squeezing the varnish entirely out of the joint when the parts are drawn together.-

Other uses for the material will be apparent to those skilled in the art.

This application is a proper division of my Patent No. 1,386,380, granted August 2,

1921, for composition of matter. Vhat I claim is:

1. A composition of matter which is impervious to and unaffected by gasoline, oils and the like and which remains substantially permanently pliable or flexible when applied in coatings or layers, said composition comprising-a solution of the precipitated product of an alkaline solution of a gum and an acid combined in homogeneous form with a fibrous inorganic body material.

2. A composition of matter which is impervious to and unaffected by gasoline, oils and the like and which remains substantially permanently pliable or flexible when applied in coatings or layers, said composition comprising an alcoholic solution of the precipitated product of an alkaline solution of a gum and sulphuric acid combined in homogeneous form with a fibrous inorganic body material.

3. A composition of matter which is impervious to and unaffected by gasoline, .oils and the like and which remains substantially permanently pliable or flexible when applied in coatings or layers, said composition comprising an alcoholic solution of the precipitated product of a caustic soda solution of shellac and sulphuric acid combined in homogeneous form with a fibrous inorganic body material.

In testimony whereof I hereby aflix my signature.

' MORTIMER I. STRAUSS. 

